Turkish investigators are looking into two Saudi Gulfstream jets that landed at the airport on 2 October. The video shows aircraft waiting on the tarmac.

Mr Khashoggi was visiting the consulate to finalise his divorce so he could marry his fiancée, Hatice Cengiz.

He is seen on the video entering the consulate while she waits outside.

Image caption Diplomatic vehicles were seen entering the consulate and driving to the Saudi consul’s residence shortly after Mr Khashoggi’s arrival

Turkey’s Sabah newspaper reports that it has identified 15 members of an intelligence team it says was involved in the Saudi’s disappearance. Among them was a forensics expert, it says.

Turkey says it will conduct a search of the Istanbul consulate, while Saudi Arabia’s foreign ministry said the country was “open to co-operation” and a search of the building could go ahead.

How Turkey is tightening the screw

By Mark Lowen, BBC News, Istanbul

With every day, leaks from the Turkish investigation are drip-fed to the media here – and hope that Jamal Khashoggi might still be alive fades further.

A government source has told me President Recep Tayyip Erdogan is sounding more cautious than the leaks, because if he were to echo the allegations that Mr Khashoggi was murdered, it would mean kicking out the Saudi ambassador and consul general by now.

So the Turks are giving the Saudis a little breathing room to put forward their argument, while releasing bits of incriminating information to tighten the screws. So far, I’m told, the Saudis haven’t been co-operating – hence Ankara releasing the names of the alleged Saudi hit squad on Wednesday.

There are plenty of gruesome rumours flying around over what happened to Jamal Khashoggi. Saudi Arabia still insists it’s all baseless. But this is not simply one side’s word against the other. It’s video evidence, photos and intelligence against a claim of innocence so far not backed up.

Who is Jamal Khashoggi?

A critic of the crown prince, Mr Khashoggi was living in self-imposed exile in the US and writing opinion pieces for the Washington Post before his disappearance.

A former editor of the al-Watan newspaper, he was for years seen as close to the Saudi royal family. He served as an adviser to senior Saudi officials.